Pneumatic power generator



Feb. 9, 1926.-

s. s. cRAMER PNEUMATIC POWER GENERATOR 3 Sheets- Sheet 1 Filed June 5; i920 81422497153 C'ramez;

Feb. 9 1926. I 1,572,269

I s. s. CRAMER PNEUMATIC POWER GENERATOR Fileq Jun 5, 1920 a Sheets- Sheet 2 Feb. 9 I926.

s. s. CRAMER PNEUMATIC POWER GENERATOR F iled June 5, 1920 I 3 Sheets-Sheet 5 4 2 7 m Inderdfor Siamlgydramen Patented ab. 9,

' UNl-TED- STATES.

PATENT TOFFICE.

sunny a. manager CAMDEN, NEW JERSEY, assume; we 110mm lt onnme COMPANY, OF GARDEN, NEW JEBSEYQA' COBI'OIBA'IION' OF DELAWARE.

nmmr'rc rowan emmna'ron.

: Application filed June 5,

To all whom it may concern:

Bejit known that I STANLEY S. (Jeanna, a citizen of the United States, res1d1ng at Camden, in the county of:C-amden and State of New Jersey, have invented certain new and useful Improvements in Pneumat c Power Generators, of which the following 1s aspecification.

This invention relates to electric motor driven pneumatic power generators, whether for creating and maintaining part al vacuums, or for producing compressed air, and the mechanical application hereinafter described has proved to be very efficient as a means for effecting the vacuum required gap between and separatingthe same for various purposes. This centrifugal fan principle .has therefore been incorporated in the presentdevice.

As in the case of all electric motor con- 'struction designed to run for extended periods of time, the-usual tendency to heat up has to be recognized, provided for and controlled, or limited, by suitable means. Likewise, the high speed at which such apparatus must run in order to. be effic ent,

creates an unavoidable hum orwhir with atone pitch and intensity dependent upon the speed of the motor" and the physical charac-- teristics of the neighboring mechanism, thus demanding in a machine of this class a. construction designed to completely muflle this sound.

Certain other factors also enter into the design of a well balanced machine, as for instance it has been found very advantageous to employ a centrally positioned motor together with'either single or multiple unit centrifugal fans of substantially equal power of displacement mounted upon the opposite ends of the motor shaft, and

so arranged that the usual central points for taking in the air face in the opposite directions, and each fan as a result operating to counteract the tendency of theother to cause 1920i Serial No. seam.

The objects of this invention therefore include broadly the provision of an improved vacuum producing mechanism, means and a method of directing the air. currents to cool the internal elements of the apparatus,

rents to completely mufiie theksounds arismg from the operation of the device, an arrangement to insure the greatest degree of balance of the parts of the device, both when stationary and in operation,.in accordance with the weight and function of the individual parts of the device, and to provide further details of construction and operation, as brought out in the following description, when read in conjunction with the accompanying drawings, in which Fig. l is a diametrical longitudinal section through one embodiment of the invention; Fig. 2 is a horizontal section on the line 22 of Fig. 1; Fig. 3 is aplan view of one 'of the fan units with a fragment of its shroud broken away; Fig. 4-. is a bottom plan view of the motor frame; and Fig. 5 is a longitudinal diametrical section of the same on the line 55of Fig. 4.

Referring to the drawings, a preferably cylindrical member 1 is provided, the'same being closed at one end by a removable disc means and a method of directing the air our- 1 2 provided with an aperture 3, in axial algnment with which is secured any suitable form of hose connection 4, while'the inner surface of said discis'provided with any suitabletype of flapper'valve 5, adapted to close the aperture 3 when the air pressure Within the member 1 is that within the coupling 4. end portion of said member is normally closed by means of a disc 6 provided with any suitable number andarrangement of apertures 7, which unite to form outlets for ail-after having passed through said mem ber following its entrance therein by means of the said aperture 3, and themember 1 together with theend closure discs 2 and 6 obviously unite to form an outer shell or container.

The member 1 is provided towards one end .with an integral radially extending flange 8, to which is removably secured a frame member hereinafter described in detail, and illustrated in Figs. 4 and 5, said frame member being separated from said flange by a suitable vibration insulating greater than he opposite 9: The said cylindrical member is furthermore provided with a second radially inwardly extending flangelO, positioned between said first flange and the .inclosing discs 2, and having secured thereto a disc 11 separated from itssupporting flange by means of a vibration insulating medium 12,

and providedcentrally with an aperture plane disc 15 provided with a cylindrical section 16 terminating in an outwardly extending radial flange 17, which .co-operates' directly with the edge'portion of the said supporting disc. Secured by suitable means to the opposite side of the flange 8 from the end closure 2, the said frame member above referred to' comprises a substantially cylindrical portion 18, upon its inner surface being provided with longitudinally extending ribs 19 and oifsets 20 having shoulders 21, against whichthe field coils 22- of the electric motor are secured by means of .set screws 23.

Said frame member nular radially outwardly extending flange portion 24 provided with circumferentially alternately positioned apertures 25 extending parallel with the axis of symmetry of the said member itself and with radially extending apertures 26, both sets of said apertures being adapted to permit and direct the passage of air currents inpredetermined paths through the device'as hereinafter described, said flange portion-being furthermore provided with diametrically opposed and aligned apertures 27 adapted to receive suitable brush holders 28, which same are removably positioned by means v of setscrews 29. I

The end portion of the said frame member nearest to the flange 8 is closed by substantially a plane section 30 provided with a central bore 31, through which extends one end portion of the armature-shaft-32, to which in turn is secured the usual commutator 33' and armature 34, said armature being .revolvably positioned substantially central with-respect to the motor field coils 22, and 'the said commutator being in alignment and slidingly contacting with brushes member is 35 supported by brush-holders 28.

"The said lane section 30 of the frame boring Jend of I the armature-shaft 32, by of 'a suitable lock+nutf39, is a cencomprising asleeve 40 also comprises an an-- of spaced apertures 61.

rthermore provided upon its.

abutting directly against the shaft-supporting portion of the ball-bearing 37, and a plane disc section 41, provided at-intervals upon its outer face with preferably Jcurved fan-blades 42, having their corresponding otherwise free edge portions connected by means of a shroud 43 having acentral aperture 44, through which extends the'annulan the extensiontherethrough of the armatureshaft 32, and at its outer free edge portion provided with a, cylindrical section 48, closed in turn at its opposite-end by means of. a

disc-like closure 49, having a central aperture 50 surrounded by an inwardly extendingcylindrical flange 52. This fan chamber,

tion 46, centrally apertured at 47 to permit together with the frame member abovede-f scribed, constitutes an inner"-casing surrounded by the outer shell 1, 2, 6.

"'The-fwall 46 is furthermore provided adjacent'to' the aperture 47 with an inwardly extending cylindrical portion.,l52, adapted to receive and position a ball-bearing 53,

rotatably supporting the said armatureeshaft and removably secured in place by means of a plug 54, which in turn has a central aperture larger than the said shaft and receives one end portion of the sleeve 55 of a centrifugal fan unit, said unit additionally comprising a radiallyextending plahe disc portion 56, provided upon the surface facing towards the closure .49 with curved fan blades 57,-connected at their otherwise free radially extending. edge portions by' means" of a shroud 58'having' a central'aperture' 59,-

into which the flange 51 is adapted to direct air currents. The said fan unit terminates considerably short of the cylindrical'por- -tion 48 and is adapted to force air outwardly .againstthe said cylindrical section, and

thence towards the armature shaft between stationary radially inwardly extending vanes 60, and through the wall 46. by way.

' Secured to the outer peripheral" surface of the motor supporting frame member is the free edge portion of a cylindricalmem v ber 62, closed at its opposite end by' mea ns of an imperforate wall 63/120 form a cup shaped baflle member, and lined throughout its fullextent bysuitable sound-insulating media 64, said bafile member being spaced from the adjacent portions of the side and end walls of the said-outershell-to provide an annular air passage between the same,

while said shell is lined by a sound-insulat ing medium 65, extending from the flange 8 to and covering the inner surface ofthe .shell closure 6, said last-named-medium being sufliciently porous to permit the'passage of air through the same and thence through the closure aperture 7.

The course followed by the air currents through this improved device is as follows :-From the usual pneumatics of a player-piano, or other pneumatically-operated musical instrument, the air is drawn through the coupling 4, past the flappervalve 5, and thence. through t e apertures in the battle 15 towards the centre of the disc currents are flung radially outwardly by the fan blades 57, and immediately thereafter are directed inwardly by the stationary.

blades 60 toward and throughfthe aperture 61 in the wall 46. At this point the air currents pass between thefield and armature windings 22 and 34 to cool the same, and thence over the surface of the commutator -33, whence they pass radially outwardly through the apertures 26 in the motor supporting frame, and thence between the cylindrical portions of the outer shell and the cup-shaped battle 1 and 62 toward and through the outlet apertures 7 in the closure 6 It is to be noted that that portion of the movable parts of this mechanism, likely to create the greatest sound by reason of their high speed of rotation and action upon the air currents, issurrounded not only b sound insulating mediums 64 and 65, but a so by a circumferentially unbroken continuously flowing jacket of air, which is operative to prevent the otherwise free passage of sound waves from the interior to the exterior of the device. -An additional marked advantage derived from the present arrangement is that the thrust of the fan-blades 42-upon the armature-shaft 32 in one direction is equally counter-acted by the thrust of the fan-blades 57 upon the said shaft in the opposite direction, thus insuring a substantially thrust-balanced bearing for the said armature-shaft and 'preventing otherwise uneven wear between contacting surfaces. Additionally, further advantage is derived from the fact thatthe air currents reverse 'their direction twice in passing by the elements of the electric driving motor, and thus in effect providing three moving air jackets, which have been hereinbefore described in 1 detail.

Having thus described my invention, what I claim and desire to protect by Letters Patent of the United States is com risin a shell havin an o enin in one 1. A pneumatic power producing device, comprising an outer shell, an inner casing, and a combined motor and fan unit within said casing and operative to cause a jacket of fluid to flow continuously between said shell and said casing throughout the longis tudinal extent of said casing while said umt is in operation.

2. A pneumatic power producing device,

com risin a'shell havin an o enin in one end portion, a transverse apertured partition within said shell, a fan unit between said partition and said end portion, a casing sup ported by said partition within and spaced away from said shell and apertured adjacent .to said partition, a fan unitwithin said casing, and means within said shell to actuate both of said fan units, to impel air currents 2 through said partition and between said shell and'said casing towards an opening. in the opposite end portion of said shell.

4. A pneumatic power producing device, comprising a shell having an opening in one end portion, a transverse apertured partition within said shell, 'a second apertured partition between said first partition and said end portion, bafile meanscovering the aperture in said second partition, afan unit between said partitions, a casing within and spaced away from said shelland apertured adjacent to said first partition, and a fan unit within said casing to impel air currents through said first partition and hetweenv said shell andsaid casing towards an outlet opening in the opposite end portion of said shell. n

5. A pneumatic-power producing device,

com llSHl" a shell havin an o enin in one vaway from said shell and apertured adjacent to the supporting partition, a fan unit within said casing to impel air currents through said first partition and between said shell and said casing towards anoutlet opening in the opposite end portion of said shell, and means within said shell to actuate said units.

lit)

6. A neumatie power producing device,

comprising a shell having an opening in one end portion, an apertured casing said opcnmg and positioned wlthln an spaced away from said shell, said casing bemg supported by the said end portion of said shell and provided with an aperture adjacent to said endportion, a. fan unit within said casing and operative to impel air currents through the aperture in said casing and throughout the extent of said casing-in the space between saideasing and said shell.

7. The combination of a container havin an inlet and an outlet, a centrally aperture 'tri insrersely extending well within said contamer, a bathe-plate positioned between said inlet and the aperture of the saidwall, a fan upon the opposite side-of said wall, a

90 second fanspaeed away from said first fan,

means to drive said fans, a channel to convey aifrom said first fan to the opposite side 0% said second fan, a channel to convey air from the nearer side of said second fan through said means to cool the latteryand' a substantially cylindrical channel surrounding said means to lead the air from said means towards said outlet, and opera tire toprovide a moving jacket of sound and heat=insulating media,

8. The combination of a container havin an inlet and an outlet, :1 fan adjacent to sai inlet, means interposed between said fan and said inlet to retard the passa e of 5 sound from said fan through said in at, a

second fan spaced away from said first fan, common means positioned between and operative to drive'said fans, a channel to convey air fromsaid first fan into the op 40 posite side of said second fan. said air pass mg by said driving means to cool the same,-'

and a channel to lead the air from said second fan towards said outlet.

1) The combination of a container having an nlet and an outlet, a fan adjacent to said inlet, means interposed between said fan and said inlet to retard the passage ofs'eund from said fan through said inlet, a's'econd' fan spaced away from said first fan,.eom-

mon means positioned between and operas tive to drive said fans, a channel to convey covering tempos air from said first fan iut'o'the opposite side i of said second fan, said air passmg by said driving means to cool the same, and a substantially cylindrical channel surrounding said driving means, to lead air from said last-named means toward said outlet, and

operative to provide a moving soundand heat-insulating media between said drivmg means and said contalner.

10. The combination of a. contalner having an inlet and an outlet, a fan adjacent to said inlet, means interposed between said fan and said inlet to retard the passage of sound through said inlet, a secondwfan spaced away froursaid first fan, a motor surrounded by a cylindrical wall and posi tioned between and operative to drive said fans, the air passing from said first fan around said motor wall and into the opposite side of said second fan, thence through spaced away from said first fan, a motor surrounded by a cylindrical wall and positioned between and operative to drive said fans, a casing surrounding said second fan and said motor and spaced away from said container, the air Iiassingfrom said first fan and thence into the. opposite side of said secondfan to equalize the axial thrust upon the motor, thence past said motor to cool the same, and around said casing 'towards said outlet. to heatand soundinsulate' said motor from said container.

'12. A pneumatic power producing device,

comprising an outer shell, an inner casing wholly surrounded by and having a portion spaced away from said shell, a motor and a fan unit within said casing: operative to cause an encircling acket of air to flow between said shell and the longitudinal extent 0t that portion of said casing containinn said fan unit. In testimony whereof I have afiixed my signature. STANLEY S. CRAMER. 

